Recently, for improved functionality, portable wireless devices provided with a communicating means built into a body thereof, for communication by means of RFID (Radio Frequency Identification), which is a contactless IC (Integrated Circuit) chip, and the like, are becoming common (for example, see Patent Document 1).
In addition, as shown in Japanese Publication No. 2004-227046, although portable wireless devices are generally provided with a retractable main antenna outside a body thereof, for communicating with a mobile communication network, portable wireless devices with a main antenna built into a body thereof, for a more sophisticated design, are becoming common recently.
Although the main antenna for communication and an antenna such as an RFID use different usable frequency bands, the antennas are disposed as far as possible from each other in order to suppress interference effects of the antennas with each other. This makes efficient use of space inside the body difficult.